The present invention relates to improvements in apparatus for manipulating rod-shaped articles of the tobacco processing industry, and more particularly to improvements in apparatus for advancing discrete articles or groups of two or more parallel articles lengthwise from a first station (such as the bottom portion of a magazine in a cigarette packing machine) to a second station, e.g., into successive receptacles of a conveyor which serves to accumulate arrays of parallel articles preparatory to confinement of such arrays in so-called hinged-lid packets or other types of containers for rod-shaped smokers' products.
It is customary to expel successive layers of plain or filter cigarettes, cigars, cigarillos or other types of rod-shaped smokers' products from the bottom portions of several neighboring upright ducts in the magazine of a packing machine into successive receptacles (e.g., open-ended enclosures having a polygonal cross-sectional outline and defining chambers for the accumulation of arrays of twenty parallel rod-shaped articles) of an endless conveyor which is normally advanced in a stepwise fashion and serves to gather successive arrays of articles and to deliver successive finished (complete) arrays to a wrapping station where the arrays are confined in sheet-like blanks of metallic foil or other types of wrapping material.
The means for expelling layers of articles from the bottom portions of neighboring ducts into successive receptacles of the conveyor normally comprises a flat reciprocable pusher which propels selected numbers of articles from the ducts and into a path wherein the articles advance lengthwise all the way into the receptacle then occupying the receiving station. The receptacles can advance seriatim past three successive magazines to accumulate arrays of articles in the so-called quincunx formation, i.e., a formation which is popular in the United States as well as in many other countries where plain or filter cigarettes are sold in the form of packets containing arrays of twenty cigarettes including two outer layers of seven cigarettes each and an intermediate or median layer of six cigarettes between the two outer layers.
Problems arise in modern high-speed packing machines wherein layers of cigarettes must be expelled from magazines at a very high frequency and must be advanced into the receptacles of an intermittently driven conveyor at an extremely high speed. As a rule, the advancing means (pusher) which propels layers of cigarettes from the bottom portions of ducts in the magazine of a packing machine into successive receptacles (e.g., hollow prismatic boxes) of a stepwise advancing (indexible) conveyor must be accelerated from zero speed to an extremely high speed and its deceleration begins before the layer of articles in front of such pusher reaches its intended ultimate position in the interior of a receptacle. The pusher must be rapidly retracted to permit cigarettes in the ducts of the magazine to descend in front of the retracted pusher before the latter proceeds to carry out a fresh forward stroke.
A layer of cigarettes which are being propelled by a rapidly advancing pusher is not decelerated in response to deceleration of the pusher but continues to advance toward and into the receptacle due to inertia of its constituents. The forward progress of a layer of articles is terminated by a suitable stop which normally causes the articles to rebound and to move backwards, i.e., counter to the direction of advancement with the pusher, so that the articles are likely to come to a halt at different distances from the stop. This is highly undesirable because the axial positions of articles forming an array in the respective receptacle are not predictable and the end portions of certain articles are likely to be defaced and/or otherwise damaged as a result of sidewise movement away from the station in front of a reciprocable pusher. For example, a filter cigarette which has rebounded on impact against a fixed stop at such station is likely to be relieved of its filter mouthpiece during sidewise movement on its way from a first layer receiving station to the next-following station or stations or to a wrapping station.